# `method`
The `method` attribute allows you to describe methods of imported JavaScript
objects. It is applied on a function that has `this` as its first parameter,
which is a shared reference to an imported JavaScript type.
```rust
#[wasm_bindgen]
extern "C" {
type Set;
#[wasm_bindgen(method)]
fn has(this: &Set, element: &JsValue) -> bool;
}
```
This generates a `has` method on `Set` in Rust, which invokes the
`Set.prototype.has` method in JavaScript.
```rust
let set: Set = ...;
let elem: JsValue = ...;
if set.has(&elem) {
...
}
```